This project supports descriptive epidemiologic studies to quantify the incidence of and mortality from cancer; to investigate variations in cancer rates by demographic factors; to examine temporal trends and geographic patterns; and to identify leads for further analytical research. In conjunction with our effort to produce national maps of cancer mortality rates, we are examining national mortality rates for 40 cancers by race, gender, and age. We analyzed the descriptive epidemiology for cancers of the oral cavity and pharynx, biliary tract, breast, cervix, testis, bladder, and kidney, as well as for multiple myeloma, and leukemia, among children, and among various racial/ethnic groups. An analysis of 178,000 lung carcinoma cases revealed that incidence rates among white and black males peaked for squamous cell carcinoma in the early 1980s, for small and large cell carcinoma in the mid-to-late 1980s, and for adenocarcinoma in the late 1980s for blacks only. Incidence among females continued to rise, although the rates of increase were diminishing. These patterns are consistent with data on temporal changes in smoking prevalence and with data on the risks of smoking for various histologic types of lung cancer. Investigation of leukemia patterns showed that incidence rates were higher among whites than blacks for three out of the four main types, whereas chronic myeloid leukemia rates were higher among blacks than whites. Incidence declined for all types except acute lymphoid leukemia, for which rates increased among all four race/sex groups. Changes in the methods of diagnosis of pancreatic cancer and the potential impact on the incidence trends were investigated; although there were substantial shifts in the source of tissue for microscopic confirmation of the diagnosis and in the type of visualization for the nonmicroscopically confirmed cases, the overall proportion microscopically confirmed changed little. In our investigation of urinary tract cancer cases who died, we found that the accuracy and representativeness of the mortality data varied by anatomic site within the urinary tract, race, sex, cause of death, age, stage at diagnosis, and length of survival.